BOSTON (AP) The Senators are heading home with a chance to eliminate the Bruins in Ottawa.

Not that they've had much trouble with them in Boston.

Bobby Ryan scored early in the third period, Craig Anderson stopped 22 shots for his fourth career postseason shutout and the Senators beat Boston 1-0 on Wednesday night for a 3-1 lead in their first-round playoff series.

It was Ottawa's fifth straight win in Boston dating to 2015 and seventh victory in eight tries - home or away - this season. Game 5 is Friday night in the Canadian capital.

"We worked so hard to get home ice for the first round of the playoffs," Senators forward Zach Smith said. "It's nice to get some wins here and go back and potentially have the chance to close it off at home."

Tuukka Rask made 26 saves for Boston, which had a goal disallowed in the second when Ottawa coach Guy Boucher challenged and the replay showed Noel Acciari was offsides.

The Bruins need a victory on Friday to force the series back to Boston.

"We'll show up, show some character," Rask said. "We've been on the other side. Us, as veterans, have to make sure the young guys don't hang their heads."

Every game so far in this best-of-seven series has been settled by a one-goal margin, including back-to-back overtimes in Games 2 and 3.

"You're not going to win 7-6 every night," Bruins forward Brad Marchand said. "You've got to be able to play any style, so that's the way it is."

The game remained scoreless until 5:49 into the third, when Erik Karlsson's shot deflected off Rask to his stick side. Ryan pulled it from his backhand to his forehand and swiped at it as Zdeno Chara dove behind Rask into the crease to try to knock the puck away from the goal line.

"There's always a game or two in the series where it's like chess. It's nice and slow and strategic moves," Anderson said. "We played our system to a T. We weathered the storm early and just stuck with it and made good on our chance in the third."

The 6-foot-9 Chara was able to reach out and prevent the first attempt from going in, but Ryan pushed it over the line with his second.

The Bruins pulled Rask with almost 2 minutes left and managed a couple of scoring chances - both from Marchand - but Anderson turned them away.

"Very good goaltending on both sides," Bruins coach Bruce Cassidy said. "Their guy was one goal better than us."

NOTES: Bruins D Colin Miller returned after missing Games 2 and 3 with an unspecified injury. ... Ottawa D Mark Borowiecki missed his second straight game. "Boro is getting closer every day," Boucher said. ... Ottawa F Tom Pyatt left after a hit from Kevan Miller early in the first. ... Bruins C Patrice Bergeron, a three-time Selke Trophy winner, was named a finalist for the award for the sixth time Wednesday.